Breathing apparatus



;K. A. GERSON BREATHING APPARATUS 2 Sheets-Sheet 1.

Filed Oct. 16, 1934 v 30 INVENTOR z 3G, 336. K. A. GERSON 2,4599% BREATHING APPARATUS Fi l ed Oct. 16, 1954 .2 SheetsSheet 2 INVENTOR w4amq- Patented June 30, 1936 UNITED STATES} PATENT OFFICE 2,045,901 I. BREATHING APPARATUS =Kurt A. Gerson, London, England Application October 16, 1924, Serial No. 748,496

' In Germany June 26,1930

7 Claims (am n piece, face mask, or head mask and Willhereinafter be referred to simply as a head fitting) and a flexible breathing chamber into which ex-. haled air is passed from the head fitting" via a charge 'of material (hereinafter referred to" as regenerating material) active upon contact with respired air either to absorb the water (H20) and carbon dioxide (CO2) contents thereof, or to1absorb H20 and CO2 and at the same time to's'upply to the air a replenishing charge of oxygen, to restore the air to its original conditio'nfThe treated air is returned to the head] fitting for further breathing, being thus continuously) in- 1 haled, exhaled, regenerated and again inhaled.

Regenerating compositions of the type'ref er'red to are well known in the art and per se form no part of this invention, for which reasons they require no detailed description. 1

A drawback of breathing apparatus of this type as known prior to my invention was. that to replace an exhausted charge ofregenerating material by a fresh charge has necessitatedthe suspension of use of the apparatus'and consequently the withdrawal of the wearer from his place of operation in the unbreathable atmos'- phere to a position where the atmosphere is breathable. 'I'his'hasbeen due to thefact that to gain access'tothe charge of regenerating material for its exchange by a fresh charge has involved opening theapparatus with consequent free access of the surrounding atmosphere into the interior thereof, coupled with the further fact that the recharging operation occuplesja period of time considerably longer .than the maximum period during which it would be safe or. pos sible for the wearer of the apparatus to dispense with the action of the regenerating material? In consequence of this difficulty the practice has been to use'a large chargeof regenerating material, but this has caused theapparatus to be somewhat bulky, and.therefore curnbersome and heavy.

. The major objects of the present invention are to overcome the foregoing and attendant difficulties in asimple and efficient manner, byproviding an apparatus in which the air-regenerat ing material can berenewed at will in the presence of unbreathable atmospheres, without danger, and quickly, surely and easily, and further to .reduce bulk and weight as compared'with prior practice.

According to the present invention, the breath= ingapparatus is characterized by the provision of a regenerating unit containing a cartridge of regenerating material which is replaceable by another charge without substantial exposure of the interior of the apparatus (that is to say the internal space occupied by the air for respiration) to the external atmosphere. By this means, as

will be understood, the foregoing practical drawbacks'o-f previously known forms of regenerative breathing apparatus, (1. e., the necessity of per= forming the operation of replacing an exhausted charge of regenerating material by a fresh charge in an atmosphere which is breathable on account of the previous necessity for opening of the apparatus) is at once avoided. Furthermore, to eliminate the'necessity of suspending use of the breathingapparatus during the recharging operation, the invention provides that said operation is capable of performance sufiiciently rapidly to enable 'the user of the breathing apparatus to change the charge of regenerating material not only without access of the external atmosphere, but'also without dofiing the head fitting.

Another feature of the invention resides in the possibility of using cartridges of regenerating material which are small relative to the usual dimensions of the canisters customarily used in these apparatus. Thus, with a breathing appa ratus incorporating this feature, the external di mensions of the part of the apparatus which ac commodates the regenerating material may be quite small, with corresponding elimination of the bulkiness and heaviness characteristic of're generative breathing apparatus as constructed, prior to my invention, or, in the case of breathing apparatus in which the part which accommodates the regenerating material is located within the breathing chamber, with corresponding increase of available air space within this chamber.

As will be appreciated by those skilled in the art, the constructional details of the invention may vary widely; that is to say, the structural form an-d'arrangement of the parts whereby, in accordance with the broadest aspect of the m vention, the cartridge or other container of re generating material is rapidly replaceable upon exhaustion by another without exposure of the interior of the apparatus to the external atmosphere surrounding it, may vary considerably,

largely in accordance with design and conver'r- V ience in any given case, relatively to the general form and arrangement of the other parts of the apparatus. 1

In one preferred form of the invention, however; the replaceable container of regenerating material is accommodated within a casing through which it is slidable with a gas' tight fit, being manually insertable into the casing at one sidethereof and ejectable therethrough at the 0 opposite side by the insertion at the first side of a second container to replace the first, which second container pushes the first out of the mounting as it is itself pushed thereinto. Such a casing is provided with openings in its wall for passage of the air therethrough. Thus there is provided a regenerating unit adapted to re ceive exhaled air, for regeneration, which achieves the objects of theinvention.

As will be understood, with this preferred constructional form of the invention, the general effect characteristic of the invention, of the op eration of replacing a spent container, or cartridge, by a fresh one being efiectual without exposure -of, the interior of the apparatus to the external atmosphere, and therefore without need for the userof the apparatus to withdraw to an atmosphere 'Which is breathable, is realized in an exceedingly simple and effective manner, for all that theuser has to do is simply to push out the spent container by inserting a fresh one in its place, in the mounting, and if, as is preferred in most, circumstances, the containers for use with the improved apparatus are in the form size the usual canister hereinbefore referred to.

The gas-tightsliding mounting for the container, according to the aforesaid preferred construction, may take any convenient form. In the caseof the container being in the form of a small cartridge, it may be a rigid tubular casing open .at both'ends. In the case, on the other hand, of the cartridge taking the form of a large container, as referred to, the mounting mayconveniently comprise two opposed saddles adapted to embrace and hold the container between them and'ported to-register with air inlet and outlet openings provided in the walls of the container, to place them in communication one with the head fitting of the breathing apparatus and the other with thebreathing chamber thereof. In such a construction, the two saddles are preferably resiliently drawn or pressed towards one another so as to embrace and retain the container between them resiliently. This arrangement, as will be appreciated, serves to ensure or enhance gas-tightness of fit as between the relatively sliding surfaces of the container and the two saddles.

;In addition, suitable packingmeans may be provided, as between said relatively sliding surfaces, still further to enhance gas-tightness of fit of these surfaces with one another, especially in the immediate neighborhood of the ports in the saddles.

Having in the foregoing outlined the principal features of the invention, several constructions embodying it will now be described by way of example of how the invention may be carried into effect, these constructions being described with reference to the accompanying drawings, of which Fig. 1 is; a vertical sectional view through one form of breathing apparatus constructed in accordance with the invention; Fig. 2, a section on the line II-QII, Fig. 1, showing a cartridge of regenerating material in operative position in the casing; Fig. :3, a View similar to Fig. 2 showing a spent cartridge being ejected by the insertion of a fresh one; Fig. 4, a vertical sectional view on a somewhat larger scale than Figs. 1 to 3, showing a larger form of container accommodated in a modified embodiment; Fig. 5, a front view of the apparatus shown in Fig. 4; Fig. 6, a similar view to Fig. 4 showing another modified construction; Fig. 7, a fragmentary section corresponding to the upper part of Fig. 4 and showing a detailed modification of construction;

.and Fig. 8, a view similar to Fig. 4 illustrating a I mounted rearwardly of opening 3, and through that opening into a cartridge 8 containing regenerating composition and disposed in casing 2. The air, passes through the cartridge and passes into connector 6, thence through a flexible tube 9 to the breathing bag II]. From the breathing bag'the air is returned to the mask through a flexible tube H, which leads to one end of a conduit member I2'the other end of which opens into connection 4. Conduit I2 is provided with a one-way valve l3 adapted to permit regenerated air to return to the mask, but to prevent exhaled air from passing directly to the breathing bag, thus compelling it topass to and through cartridge 8.

' Cartridge B is provided in its wall with inflow and outflow openings l4 and I5, respectively, positioned to register with openings 3 and 5, respectively, of casing 2. Actually the cartridge will be filled with air-regenerating composition, but in the various figures it has been omitted to avoid obscuring details. Most suitably a foraminous member I6 is disposed longitudinally of the cartridge to cause the air passing through it to be well distributed throughout the regenerating mass.

Tubular casing 2 is open at both ends so that, as already described herein,,the cartridges 8 are not only insertable into the casing from the side thereof, but also so that they may be pushed completely through the casing from the side at which they were inserted to the opposite side. Hence, upon a cartridge becoming exhausted a fresh cartridge can be pushed in its place in the mounting with simultaneous ejection of the displaced cartridge, which emerges of course from the side of the mounting opposite to the side at which the'replacing cartridge is inserted. Fig. 2 shows a cartridge 8 in operative position in the casing, while Fig. 3 shows an exhausted cartridge 8 being ejected by insertion of a fresh cartridge 8a, as just described.

The tubular casing is also arranged to have a gas-tight fit with the inserted cartridges and to maintain this fit during the sliding in of the replacing cartridge and the sliding out of thedisplaced cartridge, so that the operation of changing a cartridge is effectual with maintenance of gas-tight isolation of the interior of the apparatus from the external atmosphere surrounding it. The interior of the apparatus is, of course, closed off from the external atmosphere at one of the open ends of the tubular casing by the advancing end of the replacing cartridge Be as this is being slid into position in the casing, and at the other end by the trailing end of the ejected cartridge 8. Fig. 3 illustrates this effect.

Referring next to Figs. 4 to 8, the container, or cartridge, 20, of regenerating material in the construction shown in these figures is of approximately rectangular form in horizontal section and of the oval form shown in vertical section. It is accommodated and resilientlyheld between an opposed pair of approximately arcuate saddles M which are urged toward one another by springs 22 connected to a backing plate 23 forming part of the apparatus.

As in the case of the tubular casing 2 of the previously described construction, container 20 of the construction of Figs. 4 and '7 is slidable with a gas-tight fit into and out of operative position between the two saddles 2i The gas-tight fit, however, is ensured by the resilient pressure of the saddles toward one another upon the contacing surfaces S of the top and bottom of the container, this resilient pressure being due partly to the action of the springs 22, and partly to tension produced in a Bowden or like wire 24 anchored at its ends to the top and bottom of the backing plate, or frame member, 23. This wire is threaded through eyes 25 on inlet and outlet conduits 26 and 21 leading, respectively, to and from the interior of the container 20. The wire bears upon the outer shoulders of the saddles 2|, as shown, and is tightened by manipulation of a lever 28 pivoted at 29 to a palm 30 adapted to abut the face of the container.

' In order to ensure or enhance gas-tightness of fit between the spring-pressed saddles 2| and thetop and bottom surfaces respectively of the container 20, the said saddles are preferably provided with a resilient lining 3| of gas-impervious material, for example, absorbent material impregnated with a lubricant adapted both to impart gas-imperviousness to the absorbent material and also to serve as a lubricating agent to facilitate the insertion and simultaneous ejection of the containers into and out from position between the saddles. Alternatively, a gas-sealing and lubricating agent for the relatively sliding surfaces of the container and the saddles may be incorporated in the container wall; or again, suitable lubricating fittings may be provided in the mounting for the container, these fittings being arranged to be maintained charged with soap, grease or other lubricant.

The ends of container 20 are provided with openings 32 and 33 positioned to register with inlet and outlet conduits 26 and 21, respectively, to permit passage of the exhaled air through the regenerating composition contained in the cartridge. When handle 28 is manipulated to actuate the Bowden wire to apply tension, conduit members 26 and 2.7 are urged inwardly, and the pressureon them acts on lining 3| to seal the openings in the canister against leakage.

As shown in Fig. 5, the saddles 2| are preferably formed at the insertion end with a bell mouth,

.or outwardly turned lip, 34, to facilitate entrance of the leading end of the replacing container, as when this must be done in darkness or under other conditions which might render the replacing operation diflicult. In order to render more easy and more certain the correct positioning of the newly inserted container in the mounting (that is to say so that the inlet and outlet openings 32 and 33 in the wall of the container shall properly register with the inlet and outlet conduits 26 and 21) the arrangement is preferably such that when the container is properly positioned in the mounting the leading end is flush with the adjacent end faces of the saddles. With such an arrangement, the user of the breathing apparatus has simply to push the replacing container sufiiciently far into the space between the saddles to bring the leading end of the container flush with said end faces of the saddles, whereupon he may rest assured that the interior of his newly inserted container is in proper communication with the head fitting of the apparatus on the one hand (through conduit 26) and the breathing bag thereof (through conduit 21) on the other.

The containers are moreover preferably provided with guide ribs 35, Figs. 4 and 5, to assist in guiding the container properly into position between the saddles and thereafter to prevent the container from rotating therein. In the construction shown in Figs. 4 and 5, there are two such guide ledges, one extending along the upper part of the outer side wall of the container and the other along the lower part of the inner side Wall.

The modification of construction shown in Fig. 6 resides in this, that whereas in the arrangement shown in Figs. 4 and 7 both of the saddles 2i are resiliently mounted, in the construction shown in Fig. 6 only one of the saddles Zlw is so mounted, the other, 31, being rigidly mounted upon the carrier plate, or frame member, 23a. In addition, instead of pressing the two saddles toward one another by a tautened Bowden wire, the resiliently mounted saddle Zla is pressed toward the rigidly mounted saddle 31, and locked in operative position, by a cam lever 38 pivotally mounted upon the end of a bracket 39 projecting from the face of the carrier plate 23a. It will be appreciated, however, that any other convenient means or arrangement may be employed for resiliently pressing and locking the two saddles together upon the intervening container.

Referring again to the inlet and outlet conduits 26 and 2] which communicate respective ly with the head fitting of the apparatus and the breathing bag thereof, it will be seen from Fig. 4 that these branches (which'are of identical construction) are formed at the inner end with a flange 49 which is received behind a cooperating flange 4| formed upon a boss portion 42 of the saddle 2|, and that the pressure exerted by the tautened Bowden wire 24 thus operates to press each conduit toward its adjacent bearing surface against the canister through the intermediary of that part of the resilient liner 3| in the immediate neighborhood of the flange 40. By this means, as will be appreciated, the gas-tightness of fit as between the canister and the saddles is more especially ensured in the immediate neighborhood of theinlet and outlet conduits 26' and 27.

An alternative mode of sealing the conduits is shown in Fig. 7. As in the preceding embodiment, conduit 26a. is provided with a flange 40a which underlies a flange Ma extending inwardly from the top of boss 42a formed on saddle Zlb. In this instance, resilient liner am. is pro-vided with an opening corresponding in size to that of boss. 42a, and a resilient gasket 43 is positioned on top and on the lower side of flange 400.. As in the preceding embodiment, conduit 26a is urged downwardly by Bowden wire 24a acting through lug 25a, but in this modified construction it does so against the action of a coil spring 44 acting between flange Ma and the shoulder 45 provided on conduit 26a. It will be understood that although this embodiment has been shown and described as applied only to the inlet conduit, it is equally applicable to the outlet conduit.

When the Bowden wire is tightened it urges the conduit downwardly, so that the lower gasket 43 is pressed against the container. to form an effective gas-tight seal between the container and the conduit. With this construction, there is the advantage over the construction of Fig. 4, that when the Bowden wire is slacken'ed (by rotation of the cam lever 28) to permit or facilitate insertion of a fresh container 25! between the saddles, the flange Qila of the conduit .is positively urged by spring 44 into gas-tight lit with the boss flange did of the saddle, so that if there should happen to be leakage path for the external atmosphere past the flange ifila, this path will be effectively blocked by the upper gasket 33. Thus leakage is prevented under all conditions.

Fig. 8 shows a form of inlet conduit 23 5a somewhat difierent from that shown inFigs. 4 to '7. In this embodiment the bottom face of theconduit is convex, so that the sealing pressure created by the Bowden device is increased about the periphery of the cartridge opening 32. Of course, this modification is applicable to both the inlet and outletconduits, although shown as applied to but one.

If desired, in order to preserve in fully active condition the charge of regenerating material in the cartridge or other container, the openings in the wall of the container may be normally (that is to say, until the container is required to be used) closed by thin, air-impervious sheet material, for example, oiled-paper.

The cartridges, as also the larger form of container referred to, may of course be of any desired shape other than the shapes described in the foregoing embodiments of the invention and illustrated in the accompanying drawings.

According to the provisions of the patent statutes, I have explained the principle and mode of construction of my invention and have illustrated and described what I now consider to represent its best embodiment. However, I desire to have it understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically illustrated and described.

I claim:

1. In a self-contained breathing apparatus, an air regenerating unit for treating air exhaled by the wearer of the apparatus, the unit comprising a cartridge of air-regenerating material provided with an inlet opening for passing exhaled air into the cartridge, and with an outlet opening for egress of the treated air, and cartridge-holding means for receiving said cartridge slidably and adapted, to make a gas-tight fit with the cartridge, said cartridge being so constructed that it is replaceable when another cartridge is inserted in direct contact therewith and that such contact prevents access of external atmosphere into the apparatus during the replacing operation.

2. In a self-contained breathing apparatus, an air regenerating unit for-treating air exhaled by the wearer of the apparatus, said unit comprising a tubular casing for receiving a, cartridge of airregenerating material, and a cartridge of air-regenerating material slidably mounted within said casing and making a gas-tight fit therewith, the cartridge being provided with ports for passing exhaled air intoand removing treated air from the cartridge, and a spent cartridge being ejectable from one side of the casing by a fresh cartridge slidably inserted from the opposite side of the casing while substantially preventing access of external atmosphere into the apparatus.

3. In a self-contained breathing apparatus, an air regenerating unit for treating air exhaled by the wearer of the apparatus, said unit comprising a mounting open at its sides for slidably receiving a cartridge of air-regenerating material and provided with an inlet opening for passing exhaled air into the material and with an outlet opening for egress of the treated air, and a cartridge of air-regenerating material slidably mounted within said mounting and making a gastight fit therewith, said cartridge being provided with inlet and outlet openings adapted to register with those of said mounting, said cartridge and mounting having means cooperating to insure register of the cartridge and mounting openings when the cartridge is completely inserted in the mounting, said cartridge being so constructed that it is e'jectable from one side of the mounting when another cartridge is inserted in direct contact therewith in the other side of the mounting and that such contact prevents access of external atmosphere into the apparatus during the replacing operation.

4. In a self-contained breathing apparatus, an air regenerating unit for treating air exhaled by the wearer of the apparatus, said unit comprising a cartridge member having inlet and outlet openings and containing air regenerating material, a frame, a mounting member including a pair of opposed saddles constructed to fit against opposite ends of the cartridge and permit sliding insertion and expulsion of the cartridge laterally of the saddles, said saddles being provided with openings registering with said cartridge openings, and spring members carried by said frame urging said saddles against the ends of the cartridge, said cartridge being constructed so that it is readily ejectable when another cartridge is pushed into the saddles in contact with it and that such contact substantially prevents access of external atmosphere intofthe apparatus during the replacing operation.

5. In a self-contained breathing apparatus in accordance with claim 4, releasable tensioning means acting on a saddle to provide gas-tight fit between the saddle and the cartridge during use, release of said tensioning means permitting expulsion of the cartridge through sliding insertion of another cartridge while substantially preventing access of external atmosphere into the apparatus.

6. In a self-contained breathing apparatus according to claim 4, means associated with one of said members cooperating with the other member to insure registry of the cartridge and saddle open- ,ings directly upon complete insertion of a cartridgeJ "7. In a self-contained breathing apparatus according to claim 4, the cartridge'being provided with a rib member positioned to engage an edge of one of said saddles to insure registry of the cartridge and saddle openings directly upon complete insertion of the cartridge.

KURT A. GERSON. 

